It is known in the art to obtain trays according to thermoforming techniques, especially vacuum moulding, and to stack them one into the other. It is also known to stack trays defining an egg-box into an opened position (see Applicant's Canadian Patent No. 2,028,229). However, when trays are stacked one into the other, friction and/or air lock may be created between neighboring trays. Such interlocking of trays involves that when a tray is picked up (or denested) from the stack, one or several neighboring trays may be simultaneously picked up. This drawback becomes very important when said stack of trays is intended to fed an automated packaging and/or labelling apparatus, especially an apparatus intended to fill egg-box trays with eggs. Indeed, when the apparatus become jammed, it has to be stopped and an operator must manually remove the jammed trays from the apparatus. There is a substantial lost of productivity and of course substantial risks of damaging the apparatus.
Therefore, there is a strong need for trays that can be stacked one into the other without creation of air lock or friction between neighboring trays, to allow an easy removal of each tray from the stack of trays.
There is also a strong need for a method allowing an easy removal of each tray from a stack of trays.
There is further a strong need for a device allowing to easily pick-up each tray from a stack of trays.